You are here:
CIRCULATING NEUTROPHIL CD14 EXPRESSION REVERSE THE INVERSE ASSOCIATION OF AMBIENT PM2.5 AND PM10-2.5 ON LUNG FUNCTION IN ASTHMATIC CHILDREN
Citation:
SVENDSEN, E. R., K. B. YEATTS, D. PEDEN, S. ORTON, N. ALEXIS, J. P. CREASON, R. W. WILLIAMS, AND L. M. NEAS. CIRCULATING NEUTROPHIL CD14 EXPRESSION REVERSE THE INVERSE ASSOCIATION OF AMBIENT PM2.5 AND PM10-2.5 ON LUNG FUNCTION IN ASTHMATIC CHILDREN. Presented at American Thoracic Society International Conference, San Francisco, CA, May 19 - 23, 2007.
Description:
Background: Identifying biomarkers that predict susceptibility to size-specific PM independent of gaseous pollutants could help us better identify asthmatic subpopulations at increased risk to the adverse health effects of PM. Objective: Our objective was to assess the association between lung function and exposure to ambient levels of PM2.5 and PM10-2.5 in children with persistent asthma, and to examine if the association differed across baseline measures of inflammation and innate immune activation. Methods: We performed a panel study on a local population of 16 children with persistent asthma and assessed daily pulmonary function (% predicted PEF, FEV1) while concurrently measuring daily PM2.5 and PM10-2.5 exposure from a central site in Chapel Hill, NC. The children received a baseline medical evaluation that included the assessment of several immuno-inflammatory biomarkers in peripheral blood. Results: Lung function was significantly reduced with an increase in both PM2.5 (IQR = 8.5 ug/m3) and PM10-2.5 (IQR = 4.1 ug/m3) concentration, as expected. The negative association between PM and pulmonary function was significantly reversed for children with measurable CD14 expression (MFI) on circulating neutrophils (p < 0.0025, Figure 1). Conclusion: These findings suggest that asthmatic children with muted surface expression of CD14 on circulating neutrophils may have a decreased capacity to respond to bacterial components of PM.